The refueling of vehicles, both in civilian and military usage, usually employs a supply hose having a manually operated nozzle having a spout insertable into the vehicle tank inlet neck through an inlet port. The nozzle valve is manually operated by a handle, and a tube within the spout senses the rising fuel within the inlet neck and automatically closes the nozzle valve upon sensing the presence of the fuel level to prevent overflow and spillage.
In military usage it is sometimes desirable that refueling of the vehicle occur while the vehicle engine is operating, and in such instance it is most important that fuel spillage be prevented. Furthermore, during military operations it may be necessary to refuel vehicles in unsecured locations where it is not desirable for the operator to be exposed to possible enemy fire for as long as a refueling operation may require.
While refueling nozzles are available which may not require the immediate attention of an operator, such nozzles must employ an automatic shut-off actuator to prevent overfilling, and premature operation of the automatic fuel level sensing shut-off apparatus often occurs which requires extra attention by the operator subjecting the operator to possible danger.
It is an object of the invention to provide automatic shut-off refueling nozzle structure utilizing an automatic fluid flow shut-off sensor wherein the nozzle valve is not prematurely actuated due to false back pressures within the tank inlet.
Another object of the invention is to provide a refueling nozzle having an automatic shut-off operation wherein dependable operation is achieved and contamination and spillage are prevented.
Yet another object of the invention is to provide an automatic shut-off refueling nozzle wherein spillage is prevented even though refueling occurs without attention by the operator.
A further object of the invention is to an provide automatic refueling nozzle employing a diverger for distributing nozzle flow to prevent premature valve actuation and wherein a secondary control valve is located within the diverger and is maintained in a closed condition until the nozzle is fully connected to the tank inlet.
In the practice of the invention a conventional automatic shut-off refueling valve is utilized in conjunction with spout-mounted structure achieving the purposes of the inventive concepts. The nozzle employed with both of the disclosed embodiments of the invention is of the conventional type such as used in civilian service stations wherein the nozzle is supplied with fuel under pressure through a hose and a manually operated trigger-type valve controls flow through the nozzle spout upon the spout being inserted into the fuel tank neck through the neck port. A sensing tube within the spout having an open end adjacent the spout end senses the presence of rising fuel at the spout end and through conventional back pressure sensing and actuation means closes the nozzle valve to prevent spillage.
The structure of the invention is mounted upon the spout and includes a lug plate concentrically rotatably mounted upon the spout having lug projections for cooperating with recesses and cam surfaces defined on the tank inlet neck port. Insertion of the spout end into the tank inlet neck port permits the lugs on the lug plate to engage the port recesses and rotation of the lug plate engages the lugs with the port cam surfaces to provide a positive connection between the lug plate and the tank neck end port.
Sealing structure is mounted upon the spout in proximity to the lug plate wherein the end of the tank neck at the port sealingly engages cap or cover structure mounted on the nozzle spout to prevent contamination of the fuel during filling. A vent passage defined through the lug plate permits venting of the tank during filling and the vent structure is so located as to prevent contamination.
As a nozzle in accord with the invention is used to refuel vehicles while the engine is running, and may be refueling military vehicles while the vehicles are under enemy fire, and the operator is taking cover, it is important that premature automatic closing of the nozzle during refueling does not occur. Such valve closing will occur if the flow of fuel into the fuel tank neck is such as to create a back pressure. To avoid premature nozzle shut-off a diverger is mounted upon the end of the spout structure having a plurality of orifices defined therein through which the fuel flows during operation. The orifices within the diverger are obliquely related to the axis of the tank neck and distribute the fuel flowing into the tank neck in such a manner as to prevent back pressure and premature nozzle valve closure.
In an embodiment of the invention a control valve is located within the diverger to prevent contamination of the spout when not in use, and close the orifices of the diverger with respect to the spout interior during nonuse. The control valve within the diverger is biased in a closed direction by a low pressure compression spring, and fluid flow through the spout will compress the spring and shift the control valve to an open condition permitting flow from the spout and through the diverger. The control valve is held in a closed condition by a plurality of radially displaceable detent balls held in a locked condition within the diverger and engaging the control valve by a retainer connected to the lug plate.
Upon the lug plate being rotated to the fully connected relationship to the tank inlet port the retainer releases the detents and thereby releases the control valve for displacement by the flowing fluid. Upon the termination of fuel flow the compression spring shifts the control valve to its closed position and upon the lug plate being rotated to permit release of the nozzle structure from the fuel tank port the detents will engage the control valve to lock it in the closed condition.